Above are two charts in which Pluto is on the Midheaven. If you click on the image, you can see the details. One is TODAY, and the other is December 1, 1761, in the Age of Reason, 15 years before the American Revolution and 28 years before the French Revolution.
I put these up to illustrate Pluto, a tiny iceball whose movements have a clear effect in the lives of individuals (events can be traced by timing the transits of Pluto in one's chart), and in the life of humankind in general. These charts are set at Greenwich England, with 0 degrees Aries on the Ascendant. The reason for this is to represent all humanity's chart. Only the outer planets are shown, because they move slowly enough to affect everyone in the same manner.
The midheaven can be said to symbolize aspirations, in this case, the aspirations of mankind. Pluto moved over that point in the eighteenth century, a century of intense change and upheaval, when Europe moved from the Middle Age superstitious mindset into one of rational examination of natural phenomena. In a sense it is the time when the scientific method as we know it became the overriding consciousness. Many of the old ways were overthrown and now appear to our eyes to be alien.
We are in a similar time these days, when the ways we have lived are obsolete, but the new ways are not yet conscious. Uranus, the planet of revolution, and the new, has not yet crossed the horizon into the first house, symbolic of self-conscious awareness. In the chart of 1761, it is in that house; the new ideas were already being thought about and discussed.
Neptune, planet of glamour, mysticism, drugs and romanticism, was then in the 5th house of creativity and individuality. Now it is in the 11th house of brotherhood and the collective.
I see these sky augurs as part of the trend observable in our daily lives. We are witnessing change on a scale unprecedented in what we know of human history. Humanity must change but the change is still unconscious and formulating deep inside the collective consciousness.
Pluto could be said to have the motto, "change or die". It moves more slowly than any other planet, and where it moves, it changes everything on a very deep level. Things are never the same again in the area in which it travels. The level of change we saw in the eighteenth century will be matched, but on a higher arc of the spiral ... the "heavenly bodies" move, not in a static circle, but in a dynamic spiral. Every turn is a new experience, the same sort of change but from a different perspective.
For an astrologer's perspective, visit Astrodynamics